Chapter 13

  1. The author could not say that he proved that the busy road was the quickest since there are different variables that can affect the potential outcomes. For example when calculating the means and standard deviations on given day, some influences could impede the traffic flow such as an accident, construction, and etc. To say something is “proved”, implies that it cannot change or altered.

  2. There was a very small p-value between the sets of data regarding the travel times and this was determined to be trivial because of the hypothesis being tested and the sample size. The calculation was completed to find the p-value in order to test the hypothesis. Normally when there is a small sample size of data, only large effects will result in data results that are significant. Taking into account that the p-value was 0.001, this difference would be classified as being insignificant, therefore trivial.

  3. Besides testing hypotheses, some of the other things that statistics can be used for are: predicting probabilities (like in genetics), interpreting the results from collected data (like the quality ratings of food), or performance rates and the factors that affect it (like when certain products sell the best).

Chapter 14

  1. We say the probability of the data under the null hypothesis because on how the data will be interpreted to be true (to support the hypothesis) or how it will be analyzed to be false (to reject the hypothesis). If there is no significant change between the data, than we can say that the null hypothesis is supported. Since the probability could be affected by a supported null hypothesis (this could be due to human error), it would not be feasible to say the probability of the hypothesis.

  2. B. The null hypothesis would be the opposite in the original sentence of what is implied and supported by the statement: African American males do not have a harder time than white males hailing a taxi in New York City.

C. As compared to nationwide, hospitals in New York State do not have a higher than average Cesarean birth rates.

E. Patients taking the new chemotherapy, which is less toxic, will not have response
rates that are least as good as those on the standard chemotherapy drug, which is unpleasant.

Chapter 15

  1. It is not always true that a p-value of 0.49999 is always statistically true nor a p-value of 0.050001 is never statistically significant because it depends upon who / what organization is completing the data study. For example in chemistry calculations, the resulting data is often dependent upon the number of significant digits used. Where one scientist may get .49999, the other may round it down to 0.5 and the same with 0.050001 = 0.05.

  2. The calculation from the Michael Jordan experiment resulted in a non-significant p-value because of the original sample size. When there is a small sample size of data, only large effects will result in data results (p-values) that are significant.

  3. The connection between a criminal trial and a p-value is the probability that “something” is true since the p-value is a test of the hypothesis. For example, this can be used in connecting the characteristics from a crime scene with the probability (hypothesis proven true) that samples collected from a suspect ties him / her to the scene.